This application is a national stage application of PCT/IP2013/075746, international filing date Sep. 24, 2013, and claims priority to JP 2012-222263, filed in Japan on Oct. 4, 2012, the entire disclosures of which are hereby incorporated by reference in their entirety.
The present invention relates to an electrical connection box in which a box-shaped cover that is open downward is externally fitted from above to a main body portion including an internal circuit.
Conventionally, electrical connection boxes in which electrical components such as fuses and relays are arranged with good space efficiency are used at appropriate portions in electrical systems of automobiles and the like, and thus power supply/distribution from a battery to various electrical equipment and control thereof are efficiently performed. For example, JP 2012-100476A discloses a known example of such an electrical connection box, which has a structure in which a box-shaped cover that is open downward is externally fitted from above to a main body portion including an internal circuit configured by a printed circuit board and the like.
Incidentally, in such an electrical connection box, as shown in FIG. 5 in JP 2012-100476A, flange portions projecting outward in a collar shape are provided on side walls of the main body portion. The end surfaces of the peripheral walls of the cover that is externally fitted from above to the main body portion abut against the flange portions, and thus the cover is positioned with respect to the main body portion and held. Moreover, open gaps that are formed between the opposing surfaces of the peripheral walls of the cover and the side walls of the main body portion are covered with the flange portions from below, thus advantageously preventing water from entering the main body portion from below.
However, since the flange portions are formed to project outward in the direction orthogonal to the side walls of the main body portion, there is a problem in that, for example, when water attaching to the surface of the cover due to water splash or the like flows from the upper side to the lower side, the water is likely to accumulate on the flange portions before falling downward. In addition, since minute opposing gaps are formed between the flange portions and the end surfaces of the peripheral walls of the cover abutting against the flange portions from above as shown in FIG. 1 in JP 2012-100476A, there is a risk that water accumulating on the flange portions is led into the inside of the cover through the minute gaps by capillary action.
Moreover, it is thought that water enters the cover through fuse attaching portions and the like that are formed as openings in the upper surface of the cover, and there is a risk that water entering the cover accumulates in the opposing gaps between the flange portions and the end surfaces of the peripheral walls of the cover, and thus drainage to the outside is not promoted.